A wireless access network, such as an evolution-data optimized (EDVO) network, comprises a plurality of access nodes (AN) and a plurality of access terminals (AT) in communication with the ANs. The wireless access networks allow the ATs to communicate with each other and to a core network. A wireless AT may be a cell phone, a wireless PDA, or other device equipped with a wireless access device, whereas a wireless AN may be one or more base transceiver stations coupled to a base station controller. A wireless AT communicates with a wireless AN through an air interface, whereas the AN generally communicates with the core network via a wired connection.
In new generations of wireless access networks, Internet Protocol (IP) is being used in place of conventional time division multiplexing (TDM) as the access network technology and the wireless core network technology. Examples of wireless technologies that use IP as the access network technology include universal mobile telecommunications system (UMTS), code division multiple access 2000 (CDMA2000), and some of the fourth generation (4G) wireless technologies. In IP access network, multiple access terminals may share an access channel to communicate with an access node to gain the permission to transmit. There may be contention for the access channel (AC) by multiple ATs.